Tear-resistant fabric



Dec. 2, 1952 H, F ER 2,619,705

PEAR-RESISTANT FABRIC Filed March 22. 1952 6km 4'. (Wpum ATTORNEY Patented Dec. 2, 1952 TEAR-RESISTAN T FABRIC Boutwell H. Foster, Maplewood, N. J assignor to United States Rubber Company, New York, N. Y., a. corporation of New Jersey Application March 22, 1952,. SerialNo. 278,009

13- Claims. 1

This invention relates to a strong thin woven fabric that is highly tear-resistant, and to a coated fabric made by coating'such woven fabric.

More particularly the present invention relates to a woven textile fabric that is formed of untwisted, continuous multi-filament yarns that are free to flatten out in the fabric like miniature ribbons and give good coverage in the-fabric; so as to produce a fabric that is much lighter in weight than a fabric of comparable fabric density but formed of the same weight of twisted yarns. Such a grey fabric when coated is a number of times more tear-resistant, than prior coated: fabrics formed of the same weight of twisted yarns.

This application is a continuation-in-part of my prior application Serial No. 260,356, filed December '7, 1951, and now abandoned, which in turn is a continuation-in-part of. my earlier application Serial No. 217,929; filed March 25 1951, and now abandoned;

Textile fabrics woven of relatively flatuntwisted yarns have been made heretofore but such prior yarns have, his believed, contained a bonding agent that prevented free movement of the fibers in the fabric. Also coatedfabric's are old, and have been extensively used for years.v As

commonly constructed such coated fabrics are formed by interweaving twisted warp and weft yarns to produce a closely constructed fabric, which is then coated with rubber, pl'asticor other coatingmaterial. Such a coated fabric, unless made of heavy woven cloth, will tear readily because the coating material and' weave hold each yarn firmly in place so that when subjected to a force tending to tear the fabric, the individual yarns are prevented from moving in the fabric sufliciently to relieve the tearing stress, with the result that the tearing stress is exerted upon one yarn at a time to break it rather than upon several yarns acting together to share the stress.

The textile fabric and coated fabric contemplated by the present invention both differ substantially from those produced heretofore, in'that the present textile fabric is not" closely woven, and is not produced of round twistedyarns, but is formed of ribbon-like yarn each made up, of a number of continuous synthetic filaments which have no or very little twist in the yarn, so that they will flatten out like minute ribbons in the fabric. This makes possible the use of coarse yarns to produce-a thin fabric. Each yarn preferably has so little twist that it is not seen in the woven fabric, and as a result of this low twist or zero twist the yarns lie very flat in the fabric, to make a thin well covered fabric that is surprisingly strong.

These flat yarns are disposed in the fabric in close parallel relation to each other and may touch one another but should not abut firmly against each other, as it is important that the yarns be free to spread laterally and move in the fabric. This construction provides a somewhat loose weave, so that when the fabric is subjected to a force tending to tear it, the yarns under the greatest strain can shift in the fabric several yarn rows to cause the stress to fall upon a compact group of such yarns. Furthermore since each yarn is much wider than it is thick, it will lay fiat in the fabric, with very little crimp and form a smooth face, thin fabric. This strong, smooth surface fabric is provided with a thin coating of more or less elastic material, that will permit slight movement between the yarns in the fabric under stress. This movement of the yarns under stress in the coated fabric serves to distribute the force tending to tear such yarns. These features all cooperate to produce a thin, light weight coated fabric that is strong, waterproof, durable and highly tear-resistant.

The relatively loose weave of the present fabric, which is considered anundesirable feature in most fabrics, is taken advantage of in the construction of the present invention together with the smooth surface of the untwisted yarns to permit sufficient freedom of movement of the strong individual yarns in the fabric to reduce the strain that is likely to fall upon such individual yarns. This tendency of the yarns to shift in the textile fabric is reduced to a considerable degree by the coating applied to the fabric to make it water-proof. The high tear-resisting properties of the present coated fabric are secured largely by employing a flexible and yielding coating which permits the yarns to move enough in the fabric to share the tearing stress with adjacent yarns.

The primary object of the present invention is to provide a strong, thin, light weight fabric that has a very high tear-resistance. This is accomplished by keeping the Weight of the unit thickness of the uncoated fabric low, and when the fabric is coated by keeping low the weight of the coating used to Water-proof the fabric and help hold the yarns in place in the loosely woven fabric. By employing the fiat untwisted yarns above described a large area is covered in the fabric per unit weight of yarn, and these fiat yarns impart to the fabric a smooth fiat surface. Such a fiat surface requires less weight of coating to produce a water tight coating than does a fabric of corresponding weight but formed of round yarns. A further object is to provide a coated fabric in which the textile fabric and coating cooperate to form a water-proof fabric that is highly tear-resistant.

By using the construction of the present invention it is possible to employ relatively large denier yarns having considerable strength, and still produce a thin fabric. These high denier yarns contribute greatly to the tear-resisting properties of the fabric and relatively few yarns are required to produce a well covered fabric. When round yarns of large denier are used to increase the strength of the fabric they necessarily produce a relatively heavy fabric per unit area, and such heavy fabric requires a much heavier weight of coating to render the fabric water-proof. It is desired to point out that very fine as well as coarse untwisted yarns may be employed to produce the fabric of this invention.

The tear-resistant coated fabric contemplated by the present invention may be used for various purposes and is particularly well adapted for use in those fields where a low gauge, high strength and high tear-resistance per unit of weight are desirable. Examples of such uses are found in the manufacture of water-proof clothing, ponchos, equipment protecting shrouds, tenting, industrial tape, seat covers, upholstery material, convertible automobile tops, baby carriage hoods, luggage, awnings and in other fields.

The above and other features of the present invention will be further understood from the following description when read in connection with the accompanying drawing wherein:

Fig. 1 on an enlarged scale, is a face view of a small piece of uncoated fabric constructed in ac cordance with the present invention;

Fig. 2 on a still larger scale is a sectional View taken on the line 22 of Fig. 1; and

Fig. 3 is a face view of the fabric of Fig. 1 after it has been coated.

The fabric shown in the drawing has a square weave with one up and one down, but other weaves may be used, and as shown the same size yarns are used in the warp iii and weft i I, but if desired different size yarns may be used in the warp from those in the weft. These yarns or strands are shown in the drawing as greatly enlarged, since they are ordinarily not more than a few hundredths of an inch in width and a few thousandths of an inch thick and may be even smaller. Each yarn it, ii, is preferably formed of strong, synthetic, continuous filaments such nylon (a polyamide type of filament) Dacron (a polyester type of filament), high tenacity viscose rayon, high strength regenerated'cellulose of the type made by saponifying acetate rayon and stretching during the processing. However, other high tenacity continuous filaments such as silk may be used. Each yarn may havea thickness of from one to several filaments as desired and have a greater width than thickness. The ratio of the width of the yarn to its thickness preferably is not less than 4 to 1 and may be as great as 15 to 1 or greater in the fabric. The ratio for ordinary round yarns is of course 1 to 1. A strand H3 or H may be formed of a single untwisted yarn, or of two or more such yarns laid side by side. For example the strand it) may be an untwisted 840 denier yarn or it may comprise four 210 denier untwisted yarns. The untwisted yarns of the present fabric are cheaper than the same weight twist yarns due to the cost of twisting the latter, and the weaving cost is less since fewer warp and weft yarns need to be handled to cover a given area of fabric.

The yarns or strands herein contemplated are practically devoid of twist in that they have so little twist that it does not appear in the woven fabric, so that they will lie flat in the fabric with very little crimp as shown in Fig. 2. Each yarn may be as small as 70 denier or smaller for very light fabrics weighing only about one ounce per square yard, up to 1000 denier or more for heavier fabrics, and since these yarns are muchwider than they are thick they give good coverage in the woven fabric and form a fabric having smooth, flat faces that require only a thin film of the coating I2 to make this fabric water-proof. The number of warps and wefts in a square inch is relatively low due to the width of the individual yarns, and also to the fact that the parallel yarns may be spaced slightly from each other. This spacing of the yarns may be sufficient to form spaces between the yarns that are equal to onehalf of the width of the yarns, but in most cases the space will be a smaller percent of the yarn width and if desired the parallel fiat yarns may touch each other lightly in the fabric, but they should not abut firmly as this would prevent them from spreading in the fabric. This spacing of the yarns permits the crossing yarns to lay very flat in the woven fabric, and produces small apertures or interstices l3 through the fabric adjacent the crossing yarns. Such a flat fabric having the apertures I3 coats well and these apertures are desirable as they permit the coating to strike through the apertures and anchor the coating strongly to one or both faces of the fabric. Furthermore since the present fabric is formed of continuous filaments, there are no protruding loose fibers to cause wicking. The apertures should be small for if they are of substantial size the coating will not lay smoothly over such apertures. These features all contribute to the production of a thin, strong, durable, water-proof fabric.

The fabric of the present invention has a very high tear-resistance for its weight, and tests show that the tear-resistance of this coated fabric is about four times as great as that of the same weight coated fabric woven of round yarns made of the same continuous filaments.

The yarns l0 and H are, as above stated, so woven in the fabric that the parallel yarns are spaced a slight distance apart or touch only lightly to produce a loose weave. This loose weave has a distinct advantage in the construction of the present invention in that it permits the yarns to shift slightly in the woven fabric under strains so that a force which might break one yarn will be resisted by the combined strength of several yarns. It is important to note that this fabric is designed for use as a coated fabric, as shown in Fig. 3 of the drawing, and

that the coating serves to control the movement of the yarns in the fabric.

A distinctive feature of the loosely woven uncoated fabric is its high flexibility in the plane of the weave, due to the flatness of the yarns, low crimp, and freedom of the yarns to shift in the fabric. This property which permits a large distortion angle in the plane of the fabric, may be measured by employing apparatus such as shown and described on pages 440 and 441 of A. S. T. M. Standards on Textile Materials (with related information) of October 1946. This apparatus will show the present fabric to have a very high distortion angle.

The open weave or loose weave above mentioned permits the flat, smooth yarns to slip in the fabric. This slippage is restricted and conmentioned may be used.

trolled to the desired degree by the water-proof The coating material may be applied as a solucoating applied to the fabric. This coating mation or dispersion by dipping the fabric or by terial is indicated by 12 in Fig. 3 which shows the spreading or calendering the coating material on finished coated fabric. The coating material the fabric. The coated fabric should then be should be carefully selected in order to fulfill a number of exacting requirements and produce a strong, durable, water-proof fabric. The coating material should be tough and durable so that the coated fabric will have long life, and it should be flexible and somewhat elastic, so that when the coated fabric is subjected to a force tending to tear the same the individual yarns will be able to move slightly in the fabric to thereby cause the force tending to tear the fabric to fall upon a compact group of several yarns rather than on a. single yarn.

For the coating material indicated by I2, I can use any material capable of forming a durable, flexible, waterproof film on the surface of the woven fabric. Flexibility of the coating is imheated to dry or cure the coating if required. Since the fabric contemplated by the present invention is thin and has unusually smooth faces, due to the fact that it is formed of the ribbonlike yarns l0 and II, this fabric requires much less coating material than might be expected to fill the apertures l3 and coat the fabric with a water-proof film. This small amount of coating material helps to keep down the weight of the coated fabric. For example it is found that a several ounce coated fabric will hold air and water without leaking, even under pressure.

The strength and tear-resisting properties of the coated fabric of the present invention are extremely high per unit of fabric weight. In order that a further understanding of the construction of the present invention may b had portant since if the coating were unyielding like glass it would look the yarns in place and prethe following tables are given:

TABLE 1 Una-outed fabrics (similar to that shown. in Fig. 1)

A B C D SE ap. Kind of Filament Nylon Nylon Nylon Dacron Acetate 1. Size of yarn (denier) warp 70 210 840 210 800 2. Size of yarn (denier) weft 70 210 840 210 800 3. Warps per inch 54. 5 22. 5 38. 5 22. 5 4. Wefts per inch 53 40 20. 5 38.0 20 5. Weight, oz./sq. yd 1.02 2. 29 4. 92 2.08 4. 6. Thickness, inches .0021 00. 54 .0104 .0046 .0089 7. Thickness per unit Weight 1 00206 00236 00211 00221 00200 8. Width of yarn, inches, warp." .0111 0189 .0382 0173 .0307 9. Width of yarn, inches, Weft .0158 .0212 .0374 0165 .0335 10. Ratio, width to thickness, warp" 10. 57 7.00 7. 35 7. 52 6. 90 ll. Ratio, width to thickness, weft" 15.00 7. 85 7.19 7.17 7. 53 12. Spacebetweenyarnsinches, warp. .00788 0063 00551 00827 0138 12. Space between yarns inches, weft 00314 00433 0114 00986 0169 14. Space to width ratio, warp 710 333 144 478 .450 15. Space to width ratio, weft 199 204 305 597 504 16. Crimp percent, warp 1.25 1. 9 1. 9 6 .0 17. Crimp percent, weft 1. 25 1. 9 2. 5 6 1. 25

1 Thickness per unit weight is computed by dividing the thickness in inches by the weight of the fabric in ounces per square yards.

vent extension of the individual yarns to absor the tearing force and also prevent movement of the yarns which permits several yarns to cooperate to resist the tearing force. In this way, the remarkably inherent high tear-resistance of the base-fabric is employed to best advantage by the use of a flexible coating. Examples of suitable materials from which the coating can be formed are rubbers such as natural rubber and synthetic rubbers including neoprene, butyl rubber, rubbery copolymers of butadiene and acrylonitrile, rubbery copolymers of butadiene and styrene, etc., resins such as plasticized vinyl resins comprising a major proportion of vinyl chloride, e. g., polyvinyl chloride and copolymers of a major proportion of vinyl chloride and a minor propor- The figures in Table 1 show the characteristics of several uncoated fabrics of the present invention formed of yarns varying in weight from denier to 840 denier. These characteristics which especially adapt the base fabric for the production of a thin, strong, light-weight, highly tear-resistant coated fabric are: (a) the high ratio of the Width of yarn to the thickness of the yarn, the ratio being in the examples given approximately 7 to l; (b) the space between the yarns, which in the fabrics of this [table vary from approximately 15% to 70% of the Width of the yarns; and (c) the low ratio of thickness in inches to unit weight in ounces per square yard, this is about .002 for each fabric and shows that the fabric is exceptionally .thin for its weight per tion of a monomer copolymerizable therewith square yard, 7

7 'TABLEZ A B O D E 1. Weight, oz./sq. yd. coated... 3. 70 5. 07 9. 46 5.41 7. 64 2. Weight,floz./sq. yd. coating 2. 68 2. 78 4. 54 3.33 3.19 3. Ratio, Wt. of coating to wt.

of fabric 2. 62 1. 21 0. 92 1. 0. 72 4. Thicknessof coated fabric,

' inches .0050 .0078 .0164 .0075 0131 5. Thickness of coating, inches. .0029 0024 .0060 0029 .0042 6. Impact tear-resistance in 688 29.4 1 200 31. 2 1 220 7. 1bs., weft 8 28. 2 1 195 20. 9 1 125 8. Impact tear-resistance per unit wt., warp 1.84 5.80 21 5. 77 29 9. Impact tear resistance per unit wt., weft 1. 57 5. 56 21 3. 86 16 1 Estimated (beyond capacity of machine).

work. The figures reported as warp means that the warp yarns were broken, and the figures reported as weft means that the weft yarns were broken. 'Items 8 and 9 of this table give the tear resistance of the fabric per unit weight. This is the impact tear-resistance in inch-pounds (item 6 or 7) divided by the weight of the fabric in ounces per square yard (item 1). p The tear-resistance per unit weight (item 8 or 9) is 3.86 or more for all fabrics of Table 2 except for the very light weight fabric A. This fabric A has a weight of coating over twice that of the base fabric while the highest ratio for any of the other fabrics is l to 1.6. The coating of fabric A was heavy to meet a, Government specification on weight of coating for an ordinary type of base fabric. The tear-resistance per unit weight of fabric A can be increased by using a thinner coating.

TABLE 3 Commercial round yarn fabrics coated with vinyl resin U V W X Y Z Rip-st0p 1.85 2.85 3.47 1.12 13.75 Nylon drill sheeting sheeting sateen duck 1. Weight, oz./sq. yd., coatedm" 5.22 10.00 10. 90 8. 15.20 16.3 2. Weight, oz./sq. yd., uncoatcd" 1. 87 4.87 5.03 2. 77 9. 10.0 3. Weight, oz./sq. yd., coatlng 3. 35 5.13 5. 87 5. 73 5. 6.3 4. Ratio wt. of coating to Wt.

fabric 1. 79 1. 05 1.17 2.07 59 63 5. Thickness, inches coated fabric 0066 .0181 0184 0151 0276 0282 6. Thickness, inches uncoated fabric 00476 0131 0144 0096 0252 0245 7. Thickness, inches coating .0018 0050 0040 .0055 0024 0037 8. Thickness per unit of wt. un-

coated 00255 00269 00286 00346 00264 00245 9. Impact tear-resistance 1n.-lb., V

v 7.9 14.6 11.5 6.0 13. 7 17.6 10. 11 5. 7 8.5 7. 6 5. 0 16. 4 14. 9 unit wt, warp 1. 51 1. 46 1.05 .71 .90 1.08 12. Impact tear-resistance per unit wt., weft 1. 09 .85 .70 59 1.08 .92 13. Crimp percent uncoated, warp. 1.9 7. 5 6. 25 7. 5 11. 25 22. 3 14. Crimp percent uncoated, weft. 4. 4 8. 75 11. 25 13.8 8. 75 6. 25

The most important feature of Tabl 2 is the high impact tear-resistance of the coated fabrics. These readings were secured by employing an impact tear testing device developed by United States Rubber Company. In principle this im-' pact tear test is made by cutting a sample of fabric two inches wide, slitting it down the middle to within one inch of the end or the fabric so that th remaining one inch constitutes the length of the fabric to be torn by the testing machine. One of the one-inch wide tabs of this fabric is attached to a stationary clamp and the other to the bob of a pendulum, and these tabs should be long enough to permit the pendulum to swing free when released beyond its lowermost position. The pendulum is raised to a predetermined constant height and let fall. Near the bottom of the swing the uncut one inch of the fabric is torn and the resistance to tearing slows up the pendulum. The height to which the pendulum then swings is measured. The height to which it will swing without being impeded'by the fabric sample, starting from the same height as before, is also measured. The difference is a measure of the energy absorbed (that is, of the work done) in tearing one inch of the fabric, and can be expressed in terms of inch-poundsof The fabrics of Table 3 are all commercial fabrics woven with round yarns as distinguished from the flat yarns of the present invention. The rip-stop nylon yarn fabric is a commercial fabric sold as a high tear-resisting fabric. It is produced by introducing some 12 fine yarns in the warp and in the weft and then a heavy yarn in the warp and in the weft to add tear-resistance to the fabric, the heavy yarns are intended to act as barriers to stop a tear in the fabric. The other five fabrics of this table are different weights or different types of cotton fabrics, wherein the numeral given designates the linear yardage -per pound of the fabric; The 13.75 duck fabric is close to a commercial 8 oz. duck [weight per linear yarn based upon a width of 23 inches]. These fabrics, in order to secure the data for Table 3, were coated with substantially the same Weight of material which in most cases was less than that required for-a commercial product. Had commercial weights of coating been applied the advantages of the new product would have been exhibited to even greater degrees. An examination of the tear-resistant properties of the new fabrics ofTable 2 and that of the old fabrics of Table 3 shows that the tear-resistant properties for a given weight of the new fabrics is far superior to the tear-resistant properties for a corresponding weight of the old commercial fabrics. For example, the tear-resistance of the rip-stop nylon fabric of Table 3, which represents a commercial attempt by others to product a light weight coated fabric having good tear-resistance, whencompared with that of the fabric B of Table 2 is significant. The ratio of impact tear-resistance per unit weight for the rip-stop fabric is: warp 1.51, weft 1.09 inchpound per unit weight; whereas for the fabric B the warp is 5.80 and the weft is 5.56. When the warp yarns are torn the ratio of the first fabric to the second is 5.80 to 1.51 or 3.84; and for these same fabrics when the weft yarns are torn the ratio is 5.56 to 1.09 or 5.10. This shows that fabric B of Table 2 is about four times as tearresistant for a given weight as the nylon rip-stop fabric of Table 3. The cotton fabrics of Table 3 are representative of different types of strong cotton fabrics customarily employed for coating. Since a fabric is likely to tear in'the weakest direction the lower figures for tear-resistance per unit weight in the tables, whether warp or weft, should be compared in determining the superiority of the coated fabric of the present invention over the representative prior coated fabrics of Table 3. An examination of the weight of coating per square yard in Table 2 (item 2) and that of Table 3 (item 3) shows that the coating of Table 3 is much heavier for most examples. This is because a thicker coat is required to cover round threads than the fiat threads. Likewise an examination of the warp and weft crimp of Table 1 shows that it is much less than the warp and weft crimp of Table 3. This low crimp of Table 1 is one reason why a light Weight of coating is sufficient for the fabrics of Table 1.

It will be seen from the foregoing that the thin, strong, lightweight fabric shown in Figs. 1 and 2 coats well, and that the coated fabric has remarkably high tear-resistance for its weight, also that this unique coated fabric is well adapted for use in many fields. Where the expression untwisted yarns is used in the specification and claims this is to be construed as having so little twist that it is not noticeable in the woven fabric and does not interfere with the spreading of the filaments forming a yarn.

Having thus described my invention, what I claim and desire to protect by Letters Patent is:

l. A woven textile fabric that forms the reinforcing portion of a strong tear-resistant coated fabric, such textile fabric being formed of untwisted warp and weft singles yarns that are woven with approximately the same count per inch in the warp and weft throughout the fabric and which yarns are made up of strong, continuous, synthetic filaments that can shift relatively to each other in the yarn, such yarns being free to flatten out in the woven fabric like minute ribbons disposed in close parallel relation to each other without abutting firmly one against the other to form a well covered smooth surface fabric, whereby when this uncoated fabric is subjected to a tearing force these fiat yarns will shift in the weave a distance of four or more yarn rows and crowd together to produce a compact group having the tear-resistance strength of several such yarns.

2. A woven textile fabric formed of untwisted warp and weft singles yarns that are woven with approximately the same count per inch in the Warp and weft throughout the fabric and which yarns are made up of strong, continuous, synthetic filaments that can shift relatively to each other in the yarn, such yarns being free to fiatten out in the woven fabric like minute ribbons disposed in close parallel relation to each other Without pressing firmly one against the other to form a smooth surface fabric, whereby when this fabric is subjected to a tearing force these flat yarns will shift in the weave a distance of several yarn rows and crowd together to produce a compact group having the tear-resistance strength of several such yarns.

3. A woven textile fabric formed of untwisted Warp and weft singles yarns interwoven with a square weave and said yarns being formed of continuous textile filaments that are free to shift in the yarn to flatten out in the woven fabric like minute ribbons disposed side by side in close parallel relation without pressing hard one against the otherto form a smooth surface fabric, whereby when thisfabric is subjected to a tearing force these fiat yarns will shift in the Weave a distance of several yarn rows and crowd together to produce a compact group having the tear-resistance strength of several such yarns.

4. A woven textile fabric formed of untwisted warp and weft singles yarns of not more than denier and which yarns are made up of Strong, continuous synthetic filaments that can shift relatively to each other in the yarn, such yarns being free to flatten out in the woven fabric like minute ribbons disposed in close parallel relation to each other without abutting firmly one against the other to form a well covered smooth surface fabric that weighs not more than 1.5 ounces per square yard, and wherein the flat yarns will shift a distance of several rows and crowd together in the fabric under a tearing force to resist such force.

5. A thin, strong coated fabric that is highly tear-resistant and which is woven of untwisted warp and weft singles yarns formed of strong, continuous filaments that flatten out in the fabric so that each yarn has a width that is several times its thickness, said yarns being interwoven in spaced parallel relation to form a smooth face fabric having interstices through the fabric adjacent where the yarns cross, and the fabric being coated with a flexible water-proof material, to thereby form a flexible coated water-proof fabric that has an impact tear-resistance both longitudinally and transversely of not less than 2 inchpounds per unit weight of the coated fabric.

6. A thin, strong coated fabric that is highly tear-resistant and which is woven of untwisted warp and weft singles yarns formed of strong, continuous filaments that are free to shift and flatten out in the fabric so that each yarn has a width that is several times its thickness, said yarns being interwoven in close parallel relation without abutting firmly one against the other to form a smooth face fabric, and the fabric being coated with a flexible waterproof material, to thereby form a flexible coated waterproof fabric that has an impact tear-resistance both longitudinally and transversely of not less than 2 inchpounds per unit weight of the coated fabric.

7. The coated fabric of claim 6 in which the impact tear-resistance both longitudinally and transversely is not less than 3 inch-pounds per unit weight of the coated fabric.

8. The coated fabric of claim 6 in which the strong, continuous filaments are polyamide filaments.

9. The coated fabric of claim 6 in which the warp and weft yarns have a denier of 800 or more.

10. The coated fabric of claim 6 in which the tili c kness of the coated fabric is not more than 11. The coated fabric of claim 6 in which the width of the warp and weft yarns in the fabric is more than 5 times the thickness of such yarns.

12. A thin, strong coated fabric that is highly tear-resistant and which is woven of untwisted Warp and weft singles yarns formed of strong, continuous filaments that flatten out in the fabric so that each yarn has a width that is several times its thickness, said yarns being interwoven in close parallel relation without abutting firmly one against the other to form a smooth face fabric, and the fabric being coated with .a flexible water-proof material, to thereby form a flexible coated water-proof fabric that has an impact tear-resistance both longitudinally and. transversely of not less than 1.5 inch-pounds per unit weight of the coated fabric.

13. A woven textile fabric formed of warp and weft yarns that have very little if any twist and which yarns are made upof strong, continuous, filaments that can shift relatively to each other in the yarn they form, such yarns being free to flatten out in the woven fabric like minute ribbons that are at least four times as wide as they are thick, and disposed in close parallel relation to each other without pressing firmly one against the other to form a smooth surface fabric, whereby when the fabric is subjected to a tearing force these flat yarns will shift in the weave a distance of several yarn rows and crowd together to produce .a compact group having the tear-resistance of several such yarns.

BOUTWELL H. FOSTER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,521,055 Foster Sept. 5, 1950 

5. A THIN, STRONG COATED FABRIC THAT IS HIGHLY TEAR-RESISTANT AND WHICH IS WOVEN OF UNTWISTED WARP AND WEFT SINGLES YARNS FORMED OF STRONG, CONTINUOUS FILAMENTS THAT FLATTEN OUT IN THE FABRIC SO THAT EACH YARN HAS A WIDTH THAT IS SEVERAL TIMES ITS THICKNESS, SAID YARNS BEING INTERWOVEN IN SPACED PARALLEL RELATION TO FORM A SMOOTH FACE FABRIC HAVING INTERSTICES THROUGH THE FABRIC ADJACENT WHERE THE YARNS CROSS, AND THE FABRIC BEING COATED WITH A FLEXIBLE WATER-PROOF MATERIAL, TO THEREBY FORM A FLEXIBLE COATED WATER-PROOF FABRIC THAT HAS IMPACT TEAR-RESISTANCE BOTH LONGITUDINALLY AND TRANSVERSELY OF NOT LESS THAN 2 INCHPOUNDS PER UNIT WEIGHT OF THE COATED FABRIC. 